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lyricalwillingMécanique

22 févr. 2014 (il y a 3 années et 10 mois)

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قفرم
1

ةيثحبلا تاصخلملل جذومن :

يزيلجنإ


Title

Kinetic study on the sedimentation behavior of Na
-

and

Ca
-
kaolinite suspension in the presence of polyethyleneimine

Author
-
s


W.K. Mekhamer
, N. Al Andis
*
, M. El Shabanat


Contact lnfo

0501963869

Department

chemistry

Major

Physical
chemistry

citation

original
,

Year of
Publication

Journal of King Saud University

Publisher

Production and hosting by Elsevier

Sponsor

King saud university

Type of
Publication

E
xperimental

ISSN

………………

URI/DOI

www.ksu.edu.sa

www.sciencedirect.com

Full Text
(Yes,No)

Y
es

Key words

Flocculation; Sedimentation; Polyethyleneimine; Kaolinite; Turbidity




Abstract

Flocculation properties (settling rate, sediment
thickness, supernatant clarity)
of Na
-

and

Ca
-
kaolinite suspension have been studied in the presence of cationic
polyethyleneimine (PEI) and mixtures of NaCl or CaCl2 with PEI under
controlled conditions of pH. Two extreme kinds of qualitative sedimentatio
ns
have been observed: flocculation

sedimentation (at 0, 10 and 50 ppm PEI)
and accumulation

sedimentation (at 200, 600 and 1000 ppm PEI). It is
concluded that the highest sediment thickness and lowest turbidity were
observed for Na
-

or Ca
-
kaolinite suspen
sion at 10 ppm PEI, that is to say the
critical flocculation concentration occurred at 10 ppm PEI. The
sedimentation behaviors of Na
-

and Ca
-
kaolinite suspension in the presence
of PEI were found dependent on both pH and nature of electrolytes, while
their

flocculation was enhanced by the addition of low electrolyte
concentration (0.001 mol/l) with PEI (10 ppm).